Restarting everyday to access server

I work at a small business and recently we have an issue with out network. The set up: DSL connection is connected to a Motorola modem. A separately computer (used to monitor cameras) is connected to one of the connections on the modem and another connection is connected from the modem to a Netgear firewall (FVS336G). The netgear firewall is then connected to a Gigabit switch (GS 516T) where all the computers (Windows XP), including the server computer (Windows Server 2003) are connected. All the windows xp computers need to access files on the server throughout the day.The problem is, everyday when we come to work, we are unable to access the server files unless we restart our computers since we leave them on overnight.Whats the reason our computers get disconnected to the server overnight?Thanks in advance to anyone that can help me!

This is what i got from the event log of the server computer. This event looks like it has to do with the problem. If someone can understand whats going on based on the log, let me know how i can fix this. THanks

Heres the log----------------------------------Event Type: WarningEvent Source: NETLOGONEvent Category: NoneEvent ID: 5781Date: 1/15/2010Time: 7:14:56 AMUser: N/AComputer: SERVERDescription:Dynamic registration or deletion of one or more DNS records associated with DNS domain 'DomainDnsZones.Quickbooks.' failed. These records are used by other computers to locate this server as a domain controller (if the specified domain is an Active Directory domain) or as an LDAP server (if the specified domain is an application partition).

Possible causes of failure include: - TCP/IP properties of the network connections of this computer contain wrong IP address(es) of the preferred and alternate DNS servers - Specified preferred and alternate DNS servers are not running - DNS server(s) primary for the records to be registered is not running - Preferred or alternate DNS servers are configured with wrong root hints - Parent DNS zone contains incorrect delegation to the child zone authoritative for the DNS records that failed registration

USER ACTION Fix possible misconfiguration(s) specified above and initiate registration or deletion of the DNS records by running 'nltest.exe /dsregdns' from the command prompt or by restarting Net Logon service. Nltest.exe is available in the Microsoft Windows Server Resource Kit CD.

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